Cycle Time Exceeded Error

What does 0x809F mean?

The PLC's scan cycle time has exceeded the maximum cycle time (watch cycle time) configured in the PLC Setup. This indicates the program or I/O operations are taking too long to complete within the allowed timeframe. Flag A401.08 indicates this error.

• PLC program is too complex or inefficient, leading to excessive execution time.
• Maximum cycle time setting in PLC Setup is too low.
• High-speed interrupt function is enabled in PLC Setup, affecting Maximum Interrupt Task Processing Time in A440.

Click steps to track your progress.

1. 1

   Modify the PLC program to reduce its execution time.

2. 2

   Increase the maximum cycle time setting in the PLC Setup, reviewing the Maximum Interrupt Task Processing Time in A440.

3. 3

   Divide unused parts of the program into tasks to reduce the main cycle load.

4. 4

   Implement jumps to bypass unused instructions within tasks.

5. 5

   Disable cyclic refreshing for Special I/O Units that do not require frequent updates.